re: I may be ignorant here but....
"modems signals are not data as such. They are actually analogue calls, in the same way as voice. Granted they rely on better clock signals than voice, but are analogue none the less, so surely they should be treated as voice calls.
Like I said, may be completly wrong as I haven't used a modem for about 4 years and never on a mobile."
You are confusing the method of transportation and encoding (analogue / digital) with the content within. Lets say a modem does use analogue signals (I don't really know) that doesn't preclude it from being data. Data doesn't = digital.. radio signals are analogue, aside from a select few 'HD' broadcasts, and they carry massive amounts of data.
All that aside, an 'unlimited data plan' should be just that. this company is clearly using marketing-speak to confuse users like this poor Canuck.
The user who lives by caveat empor is correct but that doesn't excuse misleading offers and newspeak about features. consumers are what keeps these companies alive (mostly) and they should be treated fairly.